Lighting device



FIG. 1 is a perspective view, showing the new design for a lighting device;

FIG. 2 is a front view thereof;

FIG. 3 is a side view thereof;

FIG. 4 is a top view thereof; and,

FIG. 5 is a bottom view thereof.

The broken line showing of unclaimed portions of the lighting device and the dash-dot-dot lines indicating the bounds of the claimed design form no part of the claimed design. 

The ornamental design for a lighting device, as shown and described. 